Enlarging under reamer for oil or artesian wells



(No Model.) 2 Sheets-Sheet 1.

' P. H. MACK.v ENLAEGING UNDER BEAMER APOB.- OIL 0R ARTESIAN WELLS. No.496,317.

Patented Apr. 25, 1893.'

ATTOHNEYJ.

(No Model.) 2Sheets-Sheet 2.

PpH. MACK. BNLARGING UNDER RBAMER fPoR oIL 0R AMBSIAN WELLS.

No. 496,317. Pate'n'ted'Apr. 275, 1893.

llllllrmz" W/TNESSES: /N VE NTO? A TTOHN E YJ.

' UNITED STATES PATENT OFFICE.

PATRIOK H. MACK, OF BRADFORD, PENNSYLVANIA.

ENLARGINGZ UNDER REAMER FOR OIL OR ARTESiAN WELLS.

SPECIFICATION forming part Of Letters Patent N0. 496,317, dated April25, 1893. Applicationiled May 20, 1892. Serial No.433,789. (No model.)

To @ZZ whom t may'concern:

Be it known that I, PATICK H. MACK acitizen of the United States,residing in the city of Bradford, in the county of McKean and State ofPennsylvania, have invented certain new and useful Improvements inEnlarging Under Reamers for Oil or Artesian Wells; and I do herebydeclare that the following is afull, clear, and exact description of thesame, reference being had to the accompanying drawings, forming part ofthis specification, and in Which- Figure l is a longitudinal elevationof my improved tool, shown in the casing with the reaming-bits closetogether. Fig. 2 is a side elevation of the tool in a position at rightangles to that shown in Figs. l. and 3. Fig.3 is a longitudinalelevation of the tool in the well and in the same position as that shownin Fig. l, but with the reaming-bits spread apart. This position islikewise at right angles to that shown in Figs. 2 and 5. The spring isshown in section, and one side of the connection-rod clevs and a sectionof the leg are broken away. Fig. 4 is a bottom view of the tool as shownin Fig. 3. Fig. 5 is aside elevation of the tool partly in section, in aplane parallel to Fig. 2 and at right angles to Figs. l and 3. Fig. 6 isan enlarged view partly in section, of the upper piece of theconnecting-rod. Fig. 7 is an enlarged view of the lower piece of theconnecting-rod. Fig. 8 is an enlarged view of the latch. Fig. 9 is anenlarged view of a larger mandrel than that shown in Figs. 1, 3 and 5,whose use will be explained hereinafter.

My invention relates to that class of Artesian and oil welldrilling-tools known as well enlarging tools, which are used forincreasing the diameter of the well hole, below the bottom of thecasing.

In the process of drilling oil-wells, what is termed a large hole, isstarted at the top of the well and drilled down to a point below thefresh-water courses. A casing of iron pipe is thenput down to the bottomof this hole and made water-tight, and the drilling is then resumed,with drilling-bits narrower than the inside diameter of the casingthrough which the tools pass freely. The depth of these water-coursesvary in dierent localities, so that the driller has to rely on his ownjudgment as to the amount of the casing need'- ed in the well to shutoff the said water-courses. He may believe the well hole to be below allof the fresh water courses, insert the casing in the well, and proceedwith the drilling for some depth below the casing and then open otherwater veins. The usual method in such cases is to, withdraw all thecasing, extend the large hole past these lower Water veins by reaming,and then recase the well. This is not only objectionable but expensive.Moreover a strata of soft rock may be encountered, which it' the casingbe withdrawn caves in on the tools, and by continued drilling in saidstrata there is great danger of the tools becoming buried and the holeplugged.

The object of my invention is to obviate the necessity of withdrawingthe casing from the well when it becomes necessary to deepen the largehole. This I accomplish by providing a tool that will pass down throughthe casing and expand so as to enlarge the well hole below the casing tosuch a diameter as to allow the casing to be lowered to the desireddepth by adding lengths or joints to its upper end. This is particularlyessential in a well where the rock "caves in, as the casing can be keptat such a distance above the bottom of the Well as to allow theenlarging under reamer to work freely and at the same time protect thebalance of tools from the caving rock, the casing being lowered as thehole increases in depth.

Referring to the drawings-A is a screwthreaded pin for connecting myenlarging under reamer to the drilling-tools.

B, is a collar, C, is the shank, and D and E, are the legs provided withthe segmental reaming-bits F.

Secured to the reaming-bits F, by means of the bolts G are slottedplates H. The object of these slotted plates H is to prevent thereaming-bits F from spreading more than the required distance apart whenin use.

J, is a rod provided at its lower end with the mandrel J the object ofwhich is to separate the reaming-bits F and hold them the requireddistance apart when they are rea1ning the hole in the well P, and saidrod J is provided at its upper end with the clevis J 2.

K is a telescoping connecting-rod composed of two pieces, the upper oneof which is proroo` 'vided with the clevis K for the purpose ofconnecting it to the shank C, by means of Ithe bolt K2. The clevis K isiitted in the depression C. The upper part of rod K is also providedwith the socket K3 in which the reduced part Ki of the lower piece ot'the connecting-rod K works. This lower piece is also provided with theclevis K5 (see Fig. 6) which engages the correspondingly formed end ofmandrel rod J. Surrounding the connectingrod K is a spiral spring IT,whose ends bear against the collars KG and K7 formed on the respectiveparts oi' rod K.

L is a latch provided with perforations L and L2 and the projecting endL3. This latch L is inserted in the slot E ot' the legE on the side ofthe leg Ewhere it is secured by a bolt or rivet E2 passing through thehole L of latch L and the sides of said slot E. The latch is thusmovably secured to leg E. The other extremity of the latch L,iits inbetween the wings of the clevis K5 which latter is titted between thewings of the clevis J2. The latch and both clevises are pivotallysecured by the rivet M, so as to form a knuckle or toggle joint betweenthe rods Jand K, which is actuated by the latch L.

The method of operating my improved enlarging under reamer is asfollows:-After screwing the shank into the box of the augerstem, thedrilling-tools are lowered into the casing, the latch L having beenpushed down into the slot E of the leg E, the parts of rod K forcedtogether and the mandrel J raised from between the reaming-bits F,allowing the latter to be pressed together for entering the casing O. Inthis position the enlarging under reamer, can pass freely down in thecasing as shown in Fig. 2. As soon as the enlarging under reamer passesbelow the bottom of the casing O, (see Fig. the flaring edges of thereaming-bits F start to eut a shoulder in the wall of the well l". Thelatch L being now below and free from the casing O, it drops t0 itslowest position in the slot E actuated by the spring N. This movementforces the mandrel J down into the recess E3 between the reaniing-bits Fand the expansive power of the spring N, will hold it there, preventingthe reaming-bits F from being pressed together when working on the wallsof the well hole I. Then it is desired to remove the enlarging underreamer from the well, the tools are hoisted in the usual manner. As soonas the projecting end L3 of the latch L, reaches the bottom of thecasing O it is caught thereon and tripped, with the effect of forcing itinto slot E', compressing the spring N and raising the mandrel J out ofthe recess E3 between the reaming-bits F, so that the casing O may pressthe reamingbits F together and permit them to pass through as shown inFig. l. When the well has been reamed to the desired depth the casingcan either be elevated high enough to allow the enlarging tool to cutolf the shoulder on which it stands, or if the rock is soft a few blowson top of the casing, will cause the shoulder to break oft and thecasing will pass through. It will be perceived that there are twoangular steps Q and R on the inside of each reaming bit F, and in thespace between these is the recess S, formed for the mandrel J, to restin when not engaged with the reaming bits E. Bycontinued use of thetool, the reaming-bits F will wear, and the frequent dressingsconsequent thereof, will shorten them up, say to the dotted lilies T. Insuch cases the rod J and mandrel J are replaced by a similar rod U andmandrel V (see Fig. 9) said mandrel being made large enough to spreadthe reaming-bits E the desired distance apart when inserted in therecess S and when the mandrel V is raised out of the recess S and thetool assumes the position shown in Eig. 1, it will rest on the steps Q.The additional rod U which is provided with aclevis similar to J2and themandrel V, is furnished with and considered a part ofthe outfit.

Having thus described my invention, what I claim isl. In a reamer forwells, the combination ot the expansible bit, a mandrel for expandingsaid bit, suitable means for projecting the mandrel consisting of thetoggle bars, one of said bars being composed of the telescoping sectionsand having a spiral spring surrounding said sections for forcing themapart, substantially as explained.

2. In a reamer tor wells, the combination of the expansible bit, themandrel for expanding said bit, a plate for limiting the movement ofsaid bit, toggle bars for projecting the mandrel, one of said bars beingcomposed of the telescoping sections, a spiral spring surrounding saidsections for forcing them apart, and a trigger for controlling saidtoggle bars, substantially as set forth.

PATRICK II. MACK.

Witnesses:

BEN R. HAGAR, E. C. I-IEATHoo'rE.

IOO

